APPENDIX TO PART I. 



85 



tageous with several of the Bromeliacece, and 

 Lilacece, with the Citrus, and Begonia also, 

 and even with the Palmes. The same ad- 

 vantage was found in the case of almost all 

 those plants for which sand is used, in order 

 to keep the earth porous, when charcoal was 

 mixed with the soil instead of sand; the 

 vegetation was always rendered stronger and 

 more vigorous. 



" At the same time that these experiments 

 were performed with mixtures of charcoal 

 with different soils, the charcoal was also 

 used free from any addition, and in this case 

 the best results were obtained. Cuts of 

 plants from different genera took root in it 

 well and quickly; I mention here only the 

 Euphorbia fastuosa and fulgens which took 

 root in ten days, Pandanus utilis in three 

 months, P. amaryllifolius, Chamcedorea ela- 

 tior in four weeks, Piper nigrum, Begonia, 

 Ficus, Cecropia, Chiococca, Buddleya, Hakea, 

 Phyllanthus, Capparis, Launts, Stifftia, Joe- 

 quinia, Mimosa, Cactus, in from eight to ten 

 aays, and several others amounting to forty 

 species, including Ilex, and many others. 

 Leaves, and pieces of leaves, and even pe- 

 dunculi, or petioles, took root and in part 

 budded in pure charcoal. Amongst others 

 we may mention thefoliola of several of the 

 Cycadece as having taken root, as also did 

 parts of the leaves of the Begonia Telfairice, 

 and Jacaranda brasiliensis ; leaves of the 

 Euphorbia fastuosa, Oxalis Barrilieri, Ficus, 

 Cyclamen, Polyanthes, Mesembryanthemum ; 

 also the delicate leaves of the Lophospermum 

 and Martynia, pieces of a leaf of the Jlgave 

 americana; tufts of Pinus, &c.; and all with- 

 out the aid of a previously formed bud. 



" Pure charcoal acts excellently as a 

 means of curing unhealthy plants. A Do- 

 rianthes excelsa, for example, which had 

 been drooping for three years, was rendered 

 completely healthy in a very short time by 

 this means. An orange-tree which had the 

 very common disease in which the leaves 

 become yellow, acquired within four weeks 

 its healthy green colour, when the upper 

 surface of the earth was removed from the 

 pot in which it was contained, and a ring 

 of charcoal of an inch in thickness strewed 

 in its place around the periphery of the pot. 

 The same was the case with the Gardenia. 



" I should be led too far were I to state all 

 the results of the experiments which I have 

 made with charcoal. The object of this 

 paper is merely to show the general effect 

 exercised by this substance on vegetation ; 

 but the reader who takes particular interest 

 in the subject will find more extensive ob- 

 servations in the 'Jlttgemeine Deutsche Garten- 

 zeitung' of Otto and Dietrich, in Berlin; or 

 Loudon's Gardener's Magazine for March, 

 1841. 



" The charcoal employed in these experi- 

 ments was the dust-like powder of charcoal 

 from firs and pines, such as is used in the 

 forges of blacksmiths, and may be easily 

 procured in any quantity. It was found to 



have most effect when allowed to lie during 

 the winter exposed to the action of the air. 

 In order to ascertain the effects of different 

 kinds of charcoal, experiments were also 

 made upon that obtained from the hard 

 woods and peat, and also upon animal char- 

 coal, although I foresaw the probability that 

 none of them would answer so well as that 

 of pine-wood, both on account of its porosity 

 and the ease with which it is decomposed.* 



" It is superfluous to remark, that in treat- 

 ing plants in the manner here described, they 

 must be plentifully supplied with water, 

 since the air having such free access pene- 

 trates and dries the roots, so that unless this 

 precaution is taken, the failure of all such 

 experiments is unavoidable. 



" The action of charcoal consists primarily 

 in its preserving the parts of the plants with 

 which it is in contact whether they be 

 roots, branches, leaves, or pieces of leaves 

 unchanged in their vital power for a long 

 space of time, so that the plant obtains time 

 to develope the organs which are necessary 

 for its further support and propagation. 

 There can scarcely be a doubt also that the 

 charcoal undergoes decomposition ; for after 

 being: used five to six years it becomes a 

 coaly earth; and if this is the case, it must 

 yield carbon, or carbonic oxide, abundantly 

 to the plants growing in it, and thus afford 

 the principal substance necessary for the 

 nutrition of vegetables.! In what other 

 manner indeed can we explain the deep 

 green colour and great luxuriance of the 

 leaves and every part of the plants, which 

 can be obtained in no other kind of soil, ac- 

 cording to the opinion of men well qualified 

 to judge? It exercises likewise a favourable 

 influence by decomposing and absorbing the 

 matters excreted by the roots, so as to keep 

 the soil free from the putrefying substances 

 which are often the cause of the death of the 

 spongiolce. Its porosity, as well as the power 

 which it possesses 01 absorbing water with 

 rapidity, and, after its saturation, of allow- 

 ing all other water to sink through it, are 

 causes also of its favourable effects. These 

 experiments show what a close affinity the 

 component parts of charcoal have to all 

 plants, for every experiment was crowned 

 with success, although plants belonging to a 



* M. Lukas has recently repeated these experi- 

 ments, and found that the animal charcoal ob- 

 tained by the calcination of bones possesses a de- 

 cided advantage over all other kinds of charcoal, 

 which he subjected to experiment. Liebig 1 s An- 

 nalen, Sand xxxix. Heft I. S. 127. 



t As some misconception has arisen regarding 

 this explanation of the action of charcoal upon ve- 

 getation, and an idea propagated that the intro- 

 duction of these opinions into this work incorpo- 

 rated them with those of Liebig, it is necessary to 

 state that they are merely inserted here as part of 

 the papers of M. Lukas. The true explanation 

 has been given in a former part of the work, viz., 

 that charcoal possesses the power of absorbing 

 carbonic acid and ammonia from the atmosphere, 

 which serve fo; the nourishment of plants. ED. 



